Register of Antartic Marine Species (RAMS) at SCAR-MarBIN
Catalogue of Life - aims to be a comprehensive catalogue of all known species of organisms on Earth with over 1,100,000 species.
Interim Register of Marine and Nonmarine Genera (IRMNG) - constructed by Tony Rees, CSIRO Marine and Atmospheric Research and useful for checking all genera and higher taxa ranks. Contains Tony's powerful taxa matching algorithm called TAXAMATCH that can deal with spelling mistakes etc.